The present invention is in the area of physical aids for vehicle drivers, and pertains more particularly to a visual and physical barrier for indicating complete operation of a roll-up door.
There exist in the world a great number of powered roll-up doors on such as warehouses, garages, and many other sorts of buildings. These doors take many forms, such as single-panel doors as often seen for garages at residences, multiple panel doors, and flexible doors. Generally all such doors have followers of some sort that follow a guiding track as the door is raised or lowered, and typically the doors are powered, usually by electric motors, but may be manually operated as well. For purposes of this specification all such doors are included, and will be referred to as roll-up doors.
It is unfortunately a rather common occurrence that a truck driver, having pulled up to a roll-up door, and having activated the mechanism to cause the door to open, pulls ahead to drive through the door before it is fully raised, and considerable damage may result. In some cases, too, the door may stick or otherwise malfunction before it is fully raised, but after it is no longer in the limited sight of the driver, with the same end result.
There are in the art various systems for indicating to a driver that the door is fully open, such as an audible signal or a visible light activated when the door is fully open. There are also in the art breakaway systems such that a portion of a door rammed by a vehicle will break away rather than destroying the entire door and expensive drive mechanisms. In many cases, however, these systems malfunction, don""t work at all (burned out bulb for example), or are for some reason ignored by the driver. What is needed is a system that imposes a visible, physical barrier to the driver until the door is raised to a point that the vehicle can safely pass. Such a system is described in enabling detail below.
In a preferred embodiment of the present invention a system for barring entry for a vehicle having a clearance height through a door opening having a roll-up door is provided, comprising a physical barrier positionable in a first position visible to a driver of the vehicle and at least partially barring passage by the vehicle through the door opening, and in a second position not barring passage by the vehicle through the door opening, and a mechanism for moving the physical barrier from the first position to the second position. The system is characterized in that operation of the mechanism for moving the physical barrier from the first position to the second position is initiated at a point at which the roll-up door has attained a height equal to or greater than the clearance height of the vehicle.
In a preferred embodiment the physical barrier is a cantilevered bar pivoted about a pivot point at one edge of the door opening. Also in a preferred embodiment the mechanism for moving the bar comprises a linkage coupled to the bar, the linkage having an engagement element for engaging the roll-up door at the point where the roll-up door has attained a height equal to or greater than the clearance height of the vehicle.
In some embodiments a second engagement element is mounted to the roll-up door to engage the first engagement element on the linkage. Also in some embodiments graphic indicia and/or text may be placed on the physical barrier.
In another aspect of the invention a method for indicating full opening of a roll-up door to a driver of a vehicle is provided, comprising the steps of (a) mounting a physical barrier positionable in a first position visible to the driver and at least partially barring passage by the vehicle, and in a second position not barring passage by the vehicle; and (b) coupling a mechanism for moving the physical barrier from the first position to the second position to the physical barrier, in a manner that the mechanism is initiated to move the barrier from the first position to the second position at a point at which the roll-up door has attained a height equal to or greater than the clearance height of the vehicle.
In some preferred embodiments of the method the physical barrier is a cantilevered bar pivoted about a pivot point at one edge of an opening served by the roll-up door. Also in some preferred embodiments the mechanism for moving the bar comprises a linkage coupled to the bar, the linkage having an engagement element for engaging the roll-up door at the point where the roll-up door has attained a height equal to or greater than the clearance height of the vehicle.
In some embodiments a second engagement element is mounted to the roll-up door to engage the first engagement element on the linkage. Also in some embodiments graphic indicia and/or text is added to the physical barrier.